ABSTRACT
The biological effects of eicosanoids in modulating numerous physiological functions have cogently underscored the critical role of dietary n-6 polyunsaturated fatty acids (PUFA) in human health. R. T. Holman reported that dietary linolenic acid relieved neurological symptoms (numbness, weakness, periodic inability to walk, blurring of vision) in a 6-year-old girl on parenteral nutrition. Patients on a parenteral protein-rich diet, deficient in 18:3n-3, developed scaly dermatitis on the shoulders, with general skin atrophy and excoriations. Dietary linolenic acid is incorporated into phospholipids and cholesterol esters of plasma lipids in a dose-dependent manner. Tissue antioxidant status (dietary tocopherol, vitamin C, phenolics, flavanoids, selenium, glutathione, peroxidase, etc.) may greatly affect the metabolic efficacy of n-3 PUFA on eicosanoid synthesis. The species of n-3 fatty acids in the diet may also determine the threshold for the appearance of a metabolic effect. Within the immediate future marine oils represent the most practical source of n-3 PUFA.
